New concept for sustainable and efficient recovery of nutrients from thermal treatment of municipal sewage sludge
| Reference number | |
| Coordinator | SANDVIKEN ENERGI VATTEN AB |
| Funding from Vinnova | SEK 1 116 000 |
| Project duration | June 2016 - September 2018 |
| Status | Completed |
| Venture | The strategic innovation programme Bioinnovation |
Purpose and goal
The goals of this project have been achieved. The project has defined the optimum properties of an ash granule and how it could be separated from the fluidised bed including a system for pretreating the raw sludge. Estimates on necessary investment cost for adapting the existing plant to the suggested concept have been presented along with a preliminary time schedule for implementation.
Expected results and effects
The results show that the mechanical strength of the ash granule is the most critical parameter for a high efficiency of the recovery process of phosphorus from sewage sludge. A successful implementation of the concept requires further development of the properties of the granules. Based on the results from this work a new project aiming to improve the mechanical strength of the granules will be initiated during the autumn of 2018, and the project has already received financing by the Swedish Water & Wastewater Association.
Planned approach and implementation
The performance of the fluidised bed prototype and the results from combustion trials using various types of sludge qualities gave proper design criteria for the conceptual design of a phosphorus recovery system adapted to the operations at Sandviken Energi.